Chapter 12: Aquatic and Terrestrial Pollution

Point source

A pollutant that you can see and point to. Usually a single source.

Nonpoint source

A pollutant that comes from many sources such as pollution from cars in a city. You can’t point to one particular place or thing.

Dead zones

Formed in the ocean where there is low oxygen (hypoxic) caused by too many nutrients coming from the land

Oxygen sag curve

A graph of discharged pollutant and the distance from the discharge. It is usually sewage pollution but can be other things.

Endocrine disruptors

Chemicals that can mimic hormones in organisms and can cause birth defects and have been linked to developmental, reproductive, neural, immune, and other problems in animals

Wetland

Land consisting of marshes, swamps, or bogs; saturated land

Eutrophication

A body of water that has so many nutrients (fertilizers like nitrogen and phosphorus) that have run off from the land that the nutrients have "fertilized" the algae that live in the water

Hypoxic

A body of water with little to no oxygen in the water

Oligotrophic

A body of water with normal to low algae levels, high amounts of oxygen, and very few nutrients

Thermal pollution

Occurs when warm water is pumped into a lake or river, lowering the oxygen levels and harming biodiversity

Persistent organic pollutants

do not break down in the environment very quickly and can build up in the tissues and fat of animals

Bioaccumulation

POPs, like the pesticide DDT, can accumulate in the fatty tissues of animals; this is referred to as bioaccumulation

Biomagnification

When animals eat other animals and the prey have POPs that have bioaccumulated in their tissues, the POPs can magnify up the food chain. This occurs because top predators eat many different prey.

E-waste

Electronic waste like TVs, computers, phones, etc

Sanitary municipal landfill

Where solid waste from homes, businesses, and more is stored. It has a clay or plastic liner, leachate detection systems, a way for the gas to be collected or burned, and a way to make sure storm water doesn’t enter the landfill.

Recycling

Taking solid waste and turning it into something new rather than throwing it away

Composting

Taking food, yard, or other organic waste and letting it decompose to form good soil

Primary sewage treatment

The first stage of sewage treatment in which the sewage is filtered in grates and screens for items that are not liquid. In addition, the sewage is slowed down so things like eggshells and coffee grounds that also are not liquid can sink to the bottom and be disposed of in a landfill.

Secondary sewage treatment

The second stage of sewage treatment where lots of air is added so the bacteria found in the sewage can begin to consume the waste and break it down into carbon dioxide and inorganic sludge. The sludge sinks to the bottom of the tank and is disposed of as well.

Tertiary sewage treatment

The stage of sewage treatment where either chemicals like chlorine and ozone gas or UV light kills any remaining bacteria Then the water is released to a river or lake.

Lethal Dose 50%

A term used in toxicology to indicate the amount of a toxin that kills 50 percent of the organisms that are being tested

Dose-response curve

A curve plotting the relationship between the dose of a drug administered and its pharmacological effect